VISA's for Syria and who needs a VISA?

Would I need a VISA under my condition? My Grandfather came from Syria, I have his Naturalization papers when he became a US Citizen, I have his marriage certificate when he married my Grandmother. I have my Fathers birth certificate, and also his marriage certificate when he married my Mother. Now myself, I have my birth certificate, and it shows my relationship to my Grandfather. Would I still need a VISA or not? Thank you for your help.